commit | 8cf602a3f587af4acc15637878437f166db4ed3f | [log] [tgz] |
---|---|---|
author | Josh Rosen <joshrosen@databricks.com> | Mon May 06 20:08:56 2024 -0700 |
committer | Dongjoon Hyun <dhyun@apple.com> | Mon May 06 20:08:56 2024 -0700 |
tree | efd762095e16ee45c023526163918b7a26d6e1fa | |
parent | 0862f69f7be874875611b71447cc9907fb8cf9db [diff] |
[SPARK-48150][SQL] try_parse_json output should be declared as nullable ### What changes were proposed in this pull request? The `try_parse_json` expression added in https://github.com/apache/spark/pull/46141 declares improper output nullability: the `try_` version's output must be marked as nullable. This PR corrects the nullability and adds a test. ### Why are the changes needed? Incorrectly declaring an expression's output as non-nullable when it is actually nullable may lead to crashes. ### Does this PR introduce _any_ user-facing change? Yes, it affects output nullability and thus may affect query result schemas. ### How was this patch tested? New unit test cases. ### Was this patch authored or co-authored using generative AI tooling? No. Closes #46409 from JoshRosen/fix-try-parse-json-nullability. Authored-by: Josh Rosen <joshrosen@databricks.com> Signed-off-by: Dongjoon Hyun <dhyun@apple.com>
Spark is a unified analytics engine for large-scale data processing. It provides high-level APIs in Scala, Java, Python, and R, and an optimized engine that supports general computation graphs for data analysis. It also supports a rich set of higher-level tools including Spark SQL for SQL and DataFrames, pandas API on Spark for pandas workloads, MLlib for machine learning, GraphX for graph processing, and Structured Streaming for stream processing.
You can find the latest Spark documentation, including a programming guide, on the project web page. This README file only contains basic setup instructions.
Spark is built using Apache Maven. To build Spark and its example programs, run:
./build/mvn -DskipTests clean package
(You do not need to do this if you downloaded a pre-built package.)
More detailed documentation is available from the project site, at “Building Spark”.
For general development tips, including info on developing Spark using an IDE, see “Useful Developer Tools”.
The easiest way to start using Spark is through the Scala shell:
./bin/spark-shell
Try the following command, which should return 1,000,000,000:
scala> spark.range(1000 * 1000 * 1000).count()
Alternatively, if you prefer Python, you can use the Python shell:
./bin/pyspark
And run the following command, which should also return 1,000,000,000:
>>> spark.range(1000 * 1000 * 1000).count()
Spark also comes with several sample programs in the examples
directory. To run one of them, use ./bin/run-example <class> [params]
. For example:
./bin/run-example SparkPi
will run the Pi example locally.
You can set the MASTER environment variable when running examples to submit examples to a cluster. This can be spark:// URL, “yarn” to run on YARN, and “local” to run locally with one thread, or “local[N]” to run locally with N threads. You can also use an abbreviated class name if the class is in the examples
package. For instance:
MASTER=spark://host:7077 ./bin/run-example SparkPi
Many of the example programs print usage help if no params are given.
Testing first requires building Spark. Once Spark is built, tests can be run using:
./dev/run-tests
Please see the guidance on how to run tests for a module, or individual tests.
There is also a Kubernetes integration test, see resource-managers/kubernetes/integration-tests/README.md
Spark uses the Hadoop core library to talk to HDFS and other Hadoop-supported storage systems. Because the protocols have changed in different versions of Hadoop, you must build Spark against the same version that your cluster runs.
Please refer to the build documentation at “Specifying the Hadoop Version and Enabling YARN” for detailed guidance on building for a particular distribution of Hadoop, including building for particular Hive and Hive Thriftserver distributions.
Please refer to the Configuration Guide in the online documentation for an overview on how to configure Spark.
Please review the Contribution to Spark guide for information on how to get started contributing to the project.